Major Internet advertisers are financing -- sometimes unwittingly -- the spread of potentially harmful adware and spyware, according to a new Center for Democracy and Technology (CDT) finger pointing report.
The report targets mainstream advertisers whose ads appear through 180solutions, one of the world's largest developers of Internet advertising software.
According to the CDT, once the software is installed, often without consent, it tracks users' online movements and displays often unwanted popup advertisements based on the sites they visit.
Monday's CDT report focuses on advertisers doing business with 180solutions.
"Knowingly or not, these companies are fueling the spread of unwanted programs that clog people's computers, threaten privacy and tarnish the Internet experience for millions," CDT Deputy Director Ari Schwartz said during a teleconference.
"Because the adware financing model is willfully convoluted, many companies may not know where their advertising dollars are ending up."
The CDT identified 20 well-known advertisers doing business with 180solutions and attempted to contact each about their advertising policies.
"It is important to note that the advertisers we contacted may or may not have a direct relationship with 180solutions," the CDT report states. "Given the nature of the Internet advertising industry, it is possible for companies to have several intermediaries between themselves and adware distributors."
The report adds, however, "Our testing, which included the use of a packer sniffer to monitor how the ads were loaded, suggested that many of these advertisers did deal directly with 180solutions to place their ads."
Seven advertisers responded to the CDT's inquiries. Companies not responding to the CDT's inquiries included True.com, PerfectMatch, Club Med Americas, uBid, ProFlowers, GreetingCards.com, NetZero, PeoplePC, Altrec and Waterfront Media.